All children have rights to care, education, food, shelter, and more besides. The creation of children is, therefore, the creation of costly entitlements. But who, other than the parents, can be expected to share these costs? And how much can they be expected to contribute? To date, political theorists have only attended to the first question. But without a well-reasoned answer to the second question, we won’t know whether sharing should be generous or very little, equal or unequal. In this paper, I provide the first examination of the extent of cost sharing required if children are public goods. I argue that viewing children as public goods places important limits on the total costs to be fairly shared by non-parents. This casts doubt on the view, assumed by many political theorists, that the costs of all children’s entitlements must be equally shared between parents and non-parents.